Protective sleeve for collapsible tubes for holding pastes and other extrudable materials



Dec. 27, 1955 H. M. BICKLE PROTECTIVE SLEEVE FOR COLLAPSIBLE TUBES FOR HOLDING PASTES AND OTHER EXTRUDABLE MATERIALS Filed Dec. 5, 1950 oooaooaco Harry Milman liickle, HestomEngland Application December 5, 1950, Serial No. 199,208

Claims priority, application Great Britain December 15, 1949 Claims. (Cl. 222-105) This invention relates to containers formed of cardboard or other sheet material having a substantial degree of rigidity, and more particularly but not exclusively to protective covers or sleeves for collapsible tubes. for holding tooth paste, toilet cream or other extrudable material.

Such collapsible tubes are formed from a tubular body made of metal having substantially no resiliency, one end of the tubular body being provided with a head having an extrusion nozzle and the other end of the tubular body being closed by flattening the tubular body at such end and folding and crimping together the two contacting end portions. A tube thus formed tapers towards its lower end which, due to the flattening of the tube is substantially wider than the circular upper end of the tube.

In order to protect the collapsible tubes during transit and handling, they are often enclosed in protective covers or sleeves which are given a substantially wedge shape. These protective covers or sleeves have been formed from a rectangular blank of cardboard or similar material having two spaced score lines extending parallel with the longitudinal edges of the blank and also having pairs of oblique score lines, the lines of each pair extending from the upper end of the blank and converging towards the lower end to coincide with a parallel score line at the lower end, so that when the blank is bent along. theparallel score lines and the longitudinal edge portions of the blank are secured together, and the blank is then bent along the converging score lines, a container is formed which has an opening at the upper end and tapers uniformly to a straight line edge at the lower end.

I have found that these known protective sleeves, when the collapsible tube is full or nearly so, exert a consider able pressure on the lower portion of the collapsible tube with the result that when the cap is removed from the extrusion nozzle of the tube some of the contents thereof are extruded without any manual application ofpressure to the tube, and it is the primary object of this, invention to provide an improved protective cover or sleeve in which this disadvantage is substantially obviated. A further important object of my invention is to provide a D collapsible tube and protective sleeve therefor in which the tube is locked to the sleeve against axial withdrawal therefrom. Yet another object of my invention. is to provide a collapsible tube and protectivesleeve therefor in which the sleeve is secured to the tube in such a manner as to provide an assembly having a very neat appearance. A still further object of my invention is to provide an improved container or carton of general utility.

According to my invention 1 provide a tubular container formed of cardboard or other sheet material having a substantial degree of rigidity, said container at one end (in the following description appended thereto termed the lower end) having opposed portions of the wall thereof secured in juxtaposed relationship whereby such end is closed and, adjacent said end, having, in transverse section, a rapidly increasing depth and a pronited States Patent F 2,728,487 Patented Dec. 27, 1955 ice portionately decreasing width as compared with the intermediate part of the container.

In forming a protective cover or sleeve for a collapsible tube for extrudable material I may take a substantially rectangular blank of cardboard or other suitable sheet material having a substantial degree of rigidity which is provided with spaced score lines parallel with the longitudinal edges of the blank and which is also provided adjacent the lower end thereof with score lines which converge rapidly towards the parallel score lines on well-rounded or convex linesto meet the parallel score lines at points somewhat spaced from the lower end of the blank. so that, when the longitudinal edge portions of the blank are adhesively or otherwise secured together and the opposed lower endportions of the sleeve are stapled or. otherwise secured together, a sleeve is formed in which the lower end portion of the sleeve comprises two relatively wide faces which are outwardly curved or convex longitudinally and two relatively narrow faces which are inwardly curved or concave longitudinally, the sleeve thus having a rapid change in transverse section adjacent its lower end. In this manner there is obtained a sleeve which exerts substantially no pressure on the lower end of a collapsible tube inserted into the sleeve.

The said converging score lines may extend to the upper edge-0f the blank or may terminate short of such upper edge. The blank may, moreover, have additional score lines. These additional score lines may comprise a plurality of parallel score lines extending from the upper edge of the blank towards the lower edge for a short distance. only or for a substantial distance, so as to form a sleeve having at its upper end an opening which more closely approximates a circle in shape. in another form the additional score lines comprise pairs of obliquely-extending score lines, each pair of score lines converging towards a parallel score line but terminating short of the rapidly converging score lines above-mentioned.

The rapidly converging score lines may, wholly or in part, bereplaced by the edges of apertures in the blank. For example, theblankmay be provided with apertures which are intersected by the parallel score lines. The edges of suchapertures will form stops preventing withdrawal of thecollapsible tube from the sleeve and locking the tube within the sleeve.

My invention will be further described with reference to the accompanying drawing in which like reference numerals denote like parts and in which Figure 1 isa blank for the construction of one form of protective cover or sleeve for a collapsible tube;

Figure 2 is a front elevational view of a protective cover or sleeve constructed from the blank shown in Figure l andhousing a collapsible tube;

Figure 3is a partial side elevational'view of the assembly shown in Figure 2;

Figure 4 is a-partial front elevational view of the assembly shown in Figures 2 and 3 with a head piece or cap. shown in section, secured to the upper end of the collapsible tube;

Figured is a partial. front elevational view illustrating the lower endof the collapsible tube. shown in Figures 1 and. 2, prior to its insertion into the protectivecover or sleeve and prior to acorrugatingor waving operation to reduce the width of such lower end;

Figure 6 is an end view of the collapsible tube showing the lower end thereof after the corrugating or waving operation;

Figure 7 is a partial front elevational view, partly in section of the assembly shown in Figures 2 and 3, showing the lower end of the tube flattened out to lock the collapsible tube within the cover or sleeve against axial withdrawal,

Figure 8 isaslde-elevational view of one form ofcon- 3 tainer or carton constructed in accordance with my invention;

Figure 9 is a view in cross-section taken along line 9-9 of Figure 2; and

Figure 10 is a view in cross-section taken along line l10 of Figure 2.

Referring first to Figure l the blank shown therein has two score lines 11, 12 extending parallel with the longitudinal edges of the blank to provide a centre panel 13 and two side panels 14, 15, the combined width of which is somewhat greater than the width of the centre panel 13. Extending from the upper end of the blank are two pairs of further score lines 1-6, 16 and 17, 17. The score lines of each pair converge towards a parallel score line 11 or 12 and meet such score line at a point slightly spaced from the lower end of the blank as shown in the drawing, the converging score lines being straight for the greater part of their length and converging only slightly as shown or not at all and then terminating in rapidly converging well-rounded arcuate score lines 16', 16' and 17 17'. Two additional score lines 18, 19 parallel with the score lines 11, 12 extend for a short distance from the upper edge of the blank 10.

With the blank thus scored it is folded about the score lines 11, 12 and the longitudinal edge portions of the blank are adhesively or otherwise secured together, and the opposed lower end portions of the container thus formed are stapled or otherwise secured together. By applying pressure laterally to the container it may readily be opened to provide at its upper end an octagonal opening that receives a collapsible tube.

It is not necessary that the parallel score lines should be disposed as shown in Figure 1 and they could be otherwise disposed. For example the parallel score lines could be disposed to provide a centre panel and two side panels, the centre panel having the same width as one side panel and the width of the other side panel being that required to give the desired amount of overlap to the longitudinal edge portions of the blank to enable such edge portions to be secured together in overlapping relationship.

Figures 2 and 3 illustrate a cover or sleeve 22 formed from the blank 10 shown in Figure 1 and housing a collapsible tube 20. It will be noticed that, due to the rapidly converging score lines 16', 16 and 17', 17', the depth in a transverse plane of the cover or sleeve adjacent its lower end first increases very rapidly and then for the remainder of the length of the cover or sleeve increases only very slightly (see Figure 3), and that the width in a transverse plane of the cover or sleeve adjacent its lower end decreases proportionately (see Figure 2), the two wide faces of the cover or sleeve adjacent its lower end being convexly curved longitudinally and the two narrow faces of the cover or sleeve adjacent such end being concavely curved longitudinally. The greater width of the cover or sleeve adjacent its lower end accommodates the lower part of the collapsible tube which, as seen in Figure 5, is of increased width as compared with the remainder of the body portion, and thus locks the collapsible tube to the cover or sleeve against axial withdrawal therefrom.

The opposed lower end portions of the wide faces of the cover or sleeve 10 shown in Figures 2 and 3 are secured together by a U-shaped clip member 21 of metal, a plastics or other suitable material but other means for securing such end portions together may be employed. For example, one end portion of the cover or sleeve could have a downwardly-extending flap which is folded back over the other end portion and stapled, clipped, heat-sealed or otherwise secured thereto, or the said end portions of the cover or sleeve could be heat-sealed together or to the tube under pressure.

In order that the protective sleeve may fit very snugly the collapsible tube, the latter could, if desired, be proamass? vided at the upper end of its body portion with an outwardly-extending annular bead or corrugation.

In order to facilitate entrance of the collapsible tube 20 into the cover or sleeve 22 the folded and crimped lower end 23 of the collapsible tube (Figure 5) may be longitudinally corrugated or waved as shown at 23' (Figure 6) so as to reduce the width of the lower end of the tube, proferably to that of the upper end of the tube or less. After insertion into the cover or sleeve, the corrugations of the lower end of the tube are flattened out as indicated by the arrows in Figure 7. to restore such end to its original width and thus to lock the tube in the sleeve.

If desired, the upper end of the sleeve may be adhesively secured to a collapsible tube inserted therein.

With the collapsible tube housed in the protective cover or sleeve a head piece or cap may advantageously be secured to the upper end of the tube so as to cover the upper end portion of the sleeve and at least the outer part of the tubes shoulder and thus give a neater appearance to the assembly and secure the sleeve to the tube. Such head piece or cap may be made of metal or of a plastics materials which may be shrunk on to the head of the tube. In the case of a metal head piece or cap, a metal tube may be placed around the upper part of the sleeve with part of the tube projecting beyond the sleeve and the pro jecting part of the tube is spun, crimped or pressed over into engagement with the shoulder of the collapsible tube. The metal tube initially is preferably slightly conical, the tube, after application to the sleeve, being brought to cylindrical shape with the lower end of the tube pressed into the sleeve to more firmly secure the metal cap to the sleeve. In the case of a plastics cap a cylindrical tube, e. g. of viscose, may be shrunk on the sleeve and collapsible tube, the cap flange being formed during shrinking of the tube. Alternatively tape may be wound round the upper end of the sleeve whilst in a stretched condition, the cap flange being formed by a projecting portion of the tape reverting to an unstretched condition. In a further alternative, tape, which may or may not be in a stretched condition, is wound round the upper end of the sleeve and is formed to shape by application of heat and pressure, the overlapping parts of the tape being simultaneously sealed together.

Figure 4 shows the assembly of Figures 2 and 3 with a head piece or cap 24 comprising a conical portion 25 engaging the outer part of the shoulder portion of the tube 20 and a depending flange 26 extending over the upper portion of the cover or sleeve 22.

In an alternative arrangement the closure cap for the extrusion nozzle is formed with a depending skirt that extends over the shoulder of the tube and over the upper end of the sleeve.

The improved container of this invention may also be employed as a container or carton of general utility and to this end the blank may be provided with suitable transverse score lines to provide a container or carton of variable sectional area. For example, the cross-sectional area of the container may gradually decrease throughout the greater part of the length of the container or may increase from one end towards the other end and then decrease towards such end. In some cases the container may be formed with bellows folds so that the container is axially-collapsible, concertina-like.

In some cases the upper end of the container may be closed and for this purpose the upper end of the blank may be constructed similarly to the lower end. Figure 8 shows a preferred form of such a container or carton which, intermediate of its ends, is of uniform rectangular cross-section. This container is formed from a rectangular blank having two parallel score lines 27, similar to the score lines 11, 12 of Figure l, and rapidly converging score lines 28, 28 and 29, 29 similar to the score lines 16', 16' and 17 17' of Figure l at each end of the blank,

the rapidly converging score lines 28, 28 and 29, 29 being joined by score lines 34 3% extending parallel with the score lines 27. After folding about the parallel score lines and forming into a container that is closed at one end, e. g. by the clip 31, and filling the container, the other end of the container may be closed, e. g. by a similar clip 32, to form the closed container shown in Figure 8.

in certain cases the score lines provided on the blank may be such that the opening in the sleeve is rectangular or polygonal, and the sleeve or container may be formed from a blank comprising a single piece of material or a plurality of pieces of material secured together. Where the grain of the material runs longitudinally of the blank the blank may be provided with light transverse score lines in the region of the rapidly converging score lines to facilitate the desired bending of the material towards the flat at the adjacent end of the tube. It is not necessary to secure the longitudinal edges of a plane blank in overla in relationshi and thecould be secured in abutting relationship by means of an adhesive strip which is advantageously somewhat resilient.

in the construction of the improved container of this invention, instead of providing a scored blank and then folding the blank, I may take an unscored blank and shape it on a mandrel or former and then secure together the longitudinal edge portions of the blank. The improved container of my invention could also be formed from a tubular blank. Thus, in forming a protective sleeve for a collapsible tube for extrudable material I may take a tube of cardboard or the like which is cylindrical throughout its length and slide it over a collapsible tube prior to the lower end of the collapsible tube being flattened and closed. The lower ends of the tube and sleeve could then be flattened simultaneously and clipped or otherwise secured together and the side panels of the sleeve then pressed in so that the sleeve closely conforms to the contour of the collapsible tube throughout the whole length of the body portion of the tube. Alternatively the lower end of the tube could be flattened and folded first, the sleeve then slid into position, the lower end of the sleeve flattened, and the sleeve finally shaped to conform closely to the contour of the tube. To enable the sleeve to pass over the flattened end of the tube, such end could first be longitudinally corrugated or waved or the sleeve could be made slightly conical. Alternatively the lower end of one wide face of the sleeve could be slipped under the final fold of the tube end and the lower ends of the sleeve and tube secured by a clip.

I claim:

1. A protective sleeve for a collapsible tube for holding extrudable material, said sleeve being formed of card board or other sheet material with a substantial degree of rigidity and having at its non-dispensing end opposed portions secured in juxtaposed relationship to close such end, the portion of the sleeve adjacent the non-dispensing end having two opposed relatively wide faces which converge toward said end and two opposed relatively narrow faces extending between the converging wide faces, the wide faces being convexly curved and the narrow faces concavely curved with respect to the longitudinal axis of the sleeve, the portion of the sleeve adjacent the nondispensing end having said wide and narrow faces being of rectangular cross-section transversely of longitudinal axis of the sleeve increasing in width and decreasing in depth toward said non-dispensing end.

A protective sleeve as claimed in claim 1 wherein the sleeve is made from a substantially rectangular blank provided with spaced score lines extending parallel with the longitudinal edges of the blank and adjacent the nondispensing end with lines of weakness which converge rapidly on well rounded or convex lines toward the parallei score lines to meet such lines at points spaced from said end of the blank, the longitudinal edge portions of the blank being secured together.

3. A protective sleeve according to claim 1, characterized in that the said lines of weakness are provided at least in part by apertures formed in the blank.

4. The method of making a protective sleeve for a collapsibie tube for holding extrudable material which comprises iitting a sleeve which is made of cardboard or other material having substantial rigidity and which is cylindricat throughout its length over a cylindrical collapsible tube open at its lower end, closing the lower ends of the tube and the sleeve, and shaping the lower end portion of the sleeve to provide the sleeve with two opposed relatively wide faces which converge toward the lower end of the sleeve, being convexly curved with respect to the longitudinal axis of the sleeve, and also with two relatively narrow faces which extend between the wide faces, being concavely curved with respect to the longitudinal axis of the sleeve, the shaped lower end portion of the sleeve having a rectangular cross-section transversely of the longitudinal axis of the sleeve increasing in width and decreasing in depth toward the closed lower end of the sleeve.

5. The combination with a collapsible tube having a flattened lower end portion providing two opposed faces converging toward the lower end of the tube, of a protective sleeve snugly housing said collapsible tube, said sleeve being formed from cardboard or other substantially rigid material and having a closed end, the portion of the sleeve adjacent said closed end having two relatively wide faces that are convexly curved with respect to the longitudinal axis of the sleeve and two relatively narrow faces extending between the wide faces that are concavely curved with respect to the longitudinal axis of the sleeve, said portion of the sleeve adjacent said closed end being of rectangular cross-section transversely of the longitudinal axis of the sleeve increasing in width and decreasing in depth toward said closed end.

References Cited in the file of this patent UNITED STATES PATENTS 1,148,284 Booth July 27, 1915 1,526,782 Fleischer Feb. 17, 1925 2,084,273 Beach June 15, 1937 2,331,842 Moran Oct. 12, 1943 2,387,738 Bogoslowsky Oct. 30, 1945 2,400,716 Sattler May 21, 1946 2,401,784 Zahara June 11, 1946 2,535,671 Cutler Dec. 26, 1950 FOREIGN PATENTS 605,016 France Feb. 8, 1926 548,474 Great Britain Oct. 12, 1942 

